Clamp for electrical conductors



Jul 8 1924. 1500,499

T. F. JOHNSON. JR

CLAMP FOR ELECTRICAL GONDUCTORS Filed Jan. 10. 1923 2 Sheets-Sheet 1 ATTO R N EY fiufl g, a924 1.5%,499

T. F. JOHNSON, JR

. CLAMP FOR ELECTRICAL CONDUCTORS Filed Jan 10 1923 2 Sheets-Sheet 2 T F Johnson, r

INV NTOR WITNESSES ATTORNEY Patented July 8, 1924.

TOMLINSON FORT JOHNSON, JBM, 0F ATLANTA, GEORGIA.

CLAMP FOR ELECTRICAL GONDUC'TORS.

Application filed January 10, 1923. Serial No. 611,790.

To all whom it may concern Be it known that I, ToMIJNsoN F. J OHN- SON, Jr., a citizen of the United States, residing at Atlanta, in the county of Fulton and State of Georgia, have invented new and useful Improvements in Clamps for Electrical Conductors, of which the following is a specification.

This invention relates to a clamp which may be used in connection with electrical installations for coupling the main line conductor with another conductor, such for instance as a branch or switch, or a lightning arrester or some other electrical device which is to be connected temporarily or semi-permanently.

The present invention is in the nature of an improvement on the clamp which is the subject-matter of my former application No. 482,750, filed July 6, 1921.

In the manufacture and use of the clamp constructed in accordance with my former application, it has been found that extreme care is necessary in shaping and finishing the parts so that the jaws of the clamp will exert uniformly distributed pressure across the entire width of the jaws under all conditions. Frequently, the pressure exerted will be applied entirely at one edge of the gripping jaws, thus decreasing the extent of the contacting surfaces, not only resulting in a decreased capacity but also exerting a bending stress upon the eye bolt which draws the j aws-together and sometimes causing the bolt to break. The extreme accuracy which is necessary to avoid these dilficulties makes the cost of the clamp unnecessarily high for thedpurposes for which it is intended to be use The principal object of the present invention is to improve the structure of a clamp of this nature so as to eliminate the abovementioned objectionable features, and at the same time produce a practicable clamp at a minimum cost.

In carrying out the invention, I have so constructed the jaws of the clamp that they may have a free pivotal movement, and at the same time have a suflicient relative lateral movement to form a complete contact with the conductor wire when the jaws are drawn together, without it being necessary to payany particular attention to accuracy in finishing the parts. The alined openings through the jaws are made of suflicient size so that the threaded clamping pin or eye-bolt may be freely inserted there through, and a clamping nut cooperates with the screw-threaded pin to draw the jaws together, means being provided to retain the nut in operative position always ready for the insertion or the adjustment of the pin or eye-bolt. Means also are preferably provided for positively retaining all of the parts of the clamp in assembled relation so as to prevent any of them from falling out while the clamp is being applied and thus injuring the workman.

The invention will be best understood from the following detailed description, taken in connection with the accompanying drawings, in which Fig. 1 is a side elevation of the clamp in operative relation to the conductors which are to be connected.

Fig. 2 is a vertical sectional view thereof.

Fig. 3 is a side elevation looking from the right of Fig. 1.

Fig. 4 is a side elevation looking from the left of Fig. 1.

Fig. 5 is a view similar to Fig. 1, but showing a modification.

Fig. 6 is a vertical sectional view of the form shown in Fig. 5.

Fig. 7 is a detail view jaw members. 1

Fig. 8 is a detail view of member.

Figs. 9, 10 and 11 are detail views of the clamping nut.

Referring specifically to the drawings, the invention comprises a relatively stationary 'aw 1, and a movable jaw 2, the former aving at its upper end an inwardly-turned flange 3 which is provided with an elon ated opening 4 which loosely receives the reduced cylindrical end 5 of the movable jaw member 2. A cotter pin 6 may be inserted through the outer end of the reduced portion 5 to retain the movable jaw against accidental detachment and possible injury to the workman while attaching the clamp. The opening 4 is sufficiently elongated to permit the jaws to open and close about the conductor, and is also freely movable axially in order to permit the jaws to uniformly grip 'theconductor throughout the entire width of-the jaws.

of one of the the other jaw The inner faces of the jaws are preferouter or relatively movable jaw 2 is inclined outwardly, as at 10, so that the outer ends of the jaws form a converging space through which the conductor line enters the clamp. The jaw member 1 is provided with a socket 11 which is adapted to receivethe end of the conductor 12 that is to be coupled to the line conductor, and the branch conductor may be securely clamped in the iolpket by means of a set screw 13 or the The j aws 1 and 2 are provided with alined openings 14 and 15 of suflicient diameter to freely receive a screw-threaded pin or eye-bolt 16 which is formed with a circumferential flange 17 adapted to seat on a pair of lugs18 formed on the outer surface of the jaw 1. The bolt 16 is preferably formed with an eye 19 which is adapted to receive the horn of a manipulating stick that may be used for threading thebolt into its nut 20 for drawing the jaws into clamping relation with the conductor line.

The nut 20 is adapted to seatin a recess 21 formed in the outer surface of the jaw 2, and has a pair of oppositely-projecting prongs 22 and 23 which are received between pairs of cars 24 and 25 projecting from the outer surface of the jaws by means of which the nut is held against rotation while the eye-bolt is being turned. Cotter pins 26 and 2 or the like, are inserted in the pairs, of ears across the space therebetween to positively retain the nut in operative position with respect to the jaw 2 and the openings 14 and 15.

The jaw 1 at its outer end is provided with an outwardly-inclined extension 28 havmg an opening 29 therethrough by means of which the clamp may be manipulated in order to make the connection.

In Figs. 5 and 6, I have shown amodificatlon which includes all the essentialrfeatures of the clamp, and after it has once been applied in operative relation to the conductor line, will prove just as efficient as the form shown in Figs. 1 and 2. In this modified structure, the jaw 1 is provided with ears 30 and 31, between which is a seat 32 on which the inwardly-inclined nose 33 of the jaw 2 is adapted to seat and form a fulcrum about which the jaw 2 may swing both longitudinally and transversely in order to adjust itself to the conductor line 9, and firmly grip the same throughout the width of the jaws when the eye-bolt is manipulated to draw the jaws together.

From the foregoing description, it will be apparent that the clamp herein described is very simple in its construction and may be manufactured at small cost, no time will be lost in shaping the parts, and none of the clamps will have to be discarded for non-alinement, since the structure of the parts and the manner in. which they are assembled permits the jaws to automatically adjust themselves when the clamp is applied.

It will also be understood that while I have shown and described specifically the manner of carrying out the invention, the structure shown is merely illustrative and various modifications may be made therein within the scope of what is claimed, without departing from the spirit of the invention.

What is claimed is l. A clamp for electrical conductors, comprising two associated jaws, one having an inwardly-turned flange at its rear end with an openlng therethrough, the other jaw having a rearwardly-extending reduced end portion projecting through said opening and held in loose engagement therein to permit opening of the jaws, and means for clamping said jaws about an electrical conductor. I

2. A clamp for electrical conductors, comprising two associated jaws having opposed grooves extending across their adjacent faces and adapted to receive an electrical conductor wire, one of said jaws having an inwardly-turned flange disposed transversely of its rear end with an elongated opening therethrough, the other jaw having a rea-rwardly-extending reduced end portion projecting through said opening.

and adapted to rock therein to permit opening of the jaws, and means for clamping said jaws about said conductor wire.

3. A clamp for electrical conductors, comprising two associated jaws, one having an inwardly-turned flange extending across its rear end with an opening therethrough, the other jaw having a rearwardly-extending reduced end portion projecting therethrough and held in loose engagement therein to permit opening of the jaws, said jaws being provided with alined openings extending therethrough in front of the interengaging portions, and a screw-threaded pin and nut cooperating with the alined openings to clamp the jaws about an electrical conductor.

4. A clamp for electrical conductors, comprising a pair of associated jaws, one having an inwardly-turned flange at its rear end with an opening therein elongated in a direction substantially perpendicular to the meeting faces of the jaws, the other jaw having a rearwardly-extending reduced end portionprojecting through said opening and adapted to move lengthwise of said 0 ening to permit opening of the jaws, sai jaws having opposed grooves extending across their adjacent faces and adapted to receive an electrical conductor wire, said jaws being provided with alined openings extending therethrough between their interengaging rear end portions and the opposed grooves,

and a screw-threaded pin and nut cooperating with the alined openings to clamp the jaws about said wire.

5. A clamp for an electrical conductor, comprising two associated jaws, one having an inwardly-turned flange at its rear en with an opening therethrough, the other jaw having a rearwardly-extending reduced end portion projecting through said opening, a cotter pin extending through the reduced end portion in rear of the flange to retain the rear end portion in loose engagement and to permit opening of the jaws, said jaws having opposed grooves adapted to receive an electrical conductor wire, and means for clamping said jaws about the wire.

6. A clamp for electrical conductors, com prising a pair of associated jaws, one having an inwardly-turned flange at its rear end with an opening therethrough, the other jaw having a rearwardly-extending reduced end portion projecting through said opening and loosely held therein to permit opening of the jaws, one of said jaws having ears projecting from its outer face, a nut having lugs engageable between the ears, said jaws having openings therethrough in alinement with the opening through the nut, and a screw-threaded pin insertable through said openings and adapted to be threaded into the nut to draw the jaws into clamping engagement with the conductor.

7. A clamp for electrical conductors, comprising a pair of associated jaws, one having an inwardly turned flange at its rear end with an opening therethrough, the other jaw having a rearward extension projectlng through the opening and loosely'held therein to permit opening of the jaws, one of said jaws having a channel in its outer face, a nut adapted to seat in said channel, means for retaining the nut in the channel and preventing rotation thereof, said jaws aving openings therethrough in alinement with the opening through the nut, and a screw-threaded pin insertable through said openings and adapted to be threaded into the nut to draw the jaws into clamping engagement with the conductor.

8. clamp for electrical conductors, comprising a pair of associated jaws, one having an inwardly-turned flange at its rear end with an opening therethrough, the other aw having a rearward extension projecting through the opening and loosely held therein to permit opening of the jaws, one of said jaws having a channel in its outer face, a pair of ears at each end of the channel, a nut adapted to seat in the channel and having lugs engageable between the ears to retain the nut in relatively fixed position, a cotter pin insertable across each pair of ears to retain the lugs therein, said jaws having openings therethrough in alinement with the opening through the nut, and a screwthreaded pin insertable through said openings and adapted to be threaded into the nut to draw the jaws into clamping engage ment with the conductor.

9. A clamp for electrical conductors, comprising a pair of jaws movable to and from each-other and provided with alined openings extending therethrough in a direction perpendicular to the engaging facesof the jaws, one of the jaws having ears projecting from its outer face, a nut having lugs engageable with the ears while the opening through the nut is in alinement with the openings through the jaws, and a screwthreaded pin insertable through said openings and adapted to be threaded into the nut to draw the jaws into clamping engagement with the conductors.

10. A clamp for electrical conductors, comprising a pair of jaws movable to and from each other and provided with alined openings therethrough, one of said jaws having a channel in its outer face, a nut adapted to seat in said channel with its threaded opening in registry with the openings through the jaws, means for detachably retaining the nut in the channel and preventing rotation thereof, and a screwthreaded pin insertable through the openings while the nut is so retained and adapted to be threaded into said nut to draw. the jaws into clamping engagement with the conductor. v

11. A clamp for electrical conductors, comprising a pair of jaws mounted to swing to and from each other, one of said jaws having means for clamping it to a branch conductor, the other of said jaws having a channel in its outer face, a pair of ears at each end of the channel, a nut adapted to seat in the channel and having In S engageable between the ears to retain t e nut in relatively fixed position, a cotter pin insertable across each pair of ears to retain, the lugs therein, said jaws having openings therethrough in alinement with the threaded opening through the nut, and a screwthreaded pin insertable through said openings and adapted to be threaded into the nut to draw the jaws into clamping engagement with the conductor line.

12. A clamp comprising two jaws, one of said jaws having at its rear end a longitudinal opening, the other jaw extending at its rear end into said opening and having a pivotally and laterally rocking connection therewith, whereby the jaws form a firm contact throughout their width with the article held therebetween, and means for drawing the jaws into clamping position.

13. A clamp comprising two jaws, one of said jaws having at its rear end a longitudinal opening, the other jaw having at its rear end a reduced portion extending into said opening andhaving a pivotally and laterally rocking connection therewith,

whereby the jaws form a firm contact throughout their width, said jaws having alined openings therethrough substantially perpendicular to their meeting faces, a bolt of smaller diameter than the transverse dimension of said openings for 1nsert1on therethrough, and a nut cooperating with the bolt to draw the jaws into clamping position.

14. A clamp comprising a relatively fixed jaw and a movable jaw, one of said jaws having at its rear end an integral extension provided with a longitudinal opening, the other jaw having at its rear end a reduced portion extending into said opening and of somewhat smaller cross sectional dimension than the opening, whereby one jaw is movable pivotally with respect to the other to.

close the jaws and has a lateral rocking movement so as to form a firm contact throughout the width of the jaws with a In testimony that I claim the foregoing I as my own, I have hereto affixed my signature.

TOMLINSON FORT JOHNSON, JR. 

